The purpose of this contract is to provide the services of a reading center to interpret photographs from approximately 14,500 retinal examinations (including a small percentage of blind replicate photographs), performed in the epidemiological research study of the major factors contributing to the occurrence and trends of cardiovascular disease in middle-aged adults entitled "Atherosclerosis Risk in Communities Study (ARIC)". The Retinal Artery Reading Center will assist in protocol development for the performance of retinal artery examinations in the four ARIC Field Centers, and will perform measurements and interpretations of these images in a standardized and reproducible manner. The primary objective of the Retinal Artery Reading Center is to develop, implement, and monitor performance of a protocol for the retinal photography examinations within the Atherosclerosis Risk in Communities Study. The objectives of this additional component are: 1. To assess and quantitate the independent relationship between retinal arteriosclerosis and incident CVD events. 2. To examine differences between the CVD risk factor and event profiles of retinal arteriosclerosis and carotid atherosclerosis. 3. To determine the association between retinal arteriosclerosis and cerebral MRI findings, including infarct-like lesions and small white matter lesions. 4. To contrast the profiles of cerebral MRI findings associated with retinal arteriosclerosis and carotid atherosclerosis. 5. To assess the relationship between retinal arteriosclerosis and cognitive decline.